Adjustable cam



Oct. 14, '1947. T, wobDs N 2,429,084 I ADJUSTABLE cm I Filed March 1,[1945 a Sheets-Sheet 1 Fig].

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Oct. 14, 1947. WQQDSQN I 2,429,084

. A D J U S T A B L E C AM Inven or t Thomas T; Woodson,

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Oct. 14, 1947. 1'. -r. WOODSON ADJUSTABLE CAM Filed March 1, 1946 3Sheets-Sheet 3 iAGIT. o

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A//////////////////I/I/Il/I/fl 4 Inventor: Thomas T. \Xl'oodson;

His Attorney.

Patented Oct. 14, 1947 ADJUSTABLE CAM Thomas T. Woodson, Bridgeport,Conn.,' assignor to General Electric Co New York mpany, a corporation ofApplication March 1, 1946, Serial No. 651,155

The present invention relates to automatic control mechanism forinitiating and timing a cycle of operations. It is especially welladapted for use in connection with automatic domestic clothes washingmachines.

In the automatic operation of domestic washing machines, the washing ofthe clothes in soapy water is an intermediate operation which ispreceded and followed by one or more other operations. Such precedingand following operations may be each for a predetermined fixed period oftime. The intermediate washing operation, however, should be adjustableas to time so as to permit the operator to, in advance, set the lengthofthe washing time for a period suited to the clothes being washed.

The object of the present invention is to provide' an improved automaticcontrol mechanism which can be quickly and easily setto adjust anintermediate operation of a cycle of operations for the desired lengthof time; and which at the same time is simple in structure. and reliablein operation.

For a consideration of what I believe to be novel and my invention,attention is directed to the following specification and to the claimsappended thereto.

In the drawing, Fig. 1 is a side elevation, partly in section of anautomatic control mechanism embodying my invention; Fig. 2 is a rearview with parts broken away for illustrative purposes; Fig. 3 is a frontview of the control dial with parts broken away for illustrativepurposes; Fig. is a front view of the dial with parts in a positiondifferent from that of Fig. 3; Figs. 5 and 6 are views on an enlargedscale of parts of the structure showing the parts in two differentpositions; Fig. 7 isa developed view of the control cam surfaces; Figs.8 and 9 are longitudinal section views taken on line 88 ofthe developedcam surfaces as, shown in Fig. '7, illustrating parts in two differentpositions, and Fig. 10 is a perspective view of the two members which'goto make up the ca surfaces.

"Referring to the drawing, 1 indicates a back plate or base on which ismounted a suitable timing motor 2 connected through reduction gearing 3to a timing gear 4 which has its hub keyed to a timing shaft 5. Thegearing is proportioned to turn timing shaft 5 at a desired speed. Forexample,cne revolution in forty-five minutes may be satisfactory for ausual washing machine cycle. Shaft 5 is rotatably carried in a sleeve 6journaled in a hub 1 on plate I. At its left-hand end (Fig. 1.) .sleev;6 i p videclwi l an i t al flange 8 3 Claims. (01. 74-568) which at itsperiphery carries a friction clutch ring 9 which engages the face ofgear 4. The friction clutch ring is pressed into engagement with theface of gear 4 by a spring l0 positioned between gear 4 and a collar IIon the adjacent end of shaft 5, the other end of shaft 5 having a flangel2 which abuts the end of sleeve 5. Thus it will be seen thattimingshaft 5 is connected to sleeve 6 through a spring loaded diskclutch.

Fixed on plate I is a series of electric switches l3, seven being shownin the present instance. They are arranged in a straight line. Theswitches have operating buttons [4 which are biased to an out positionand are pushed inward against the biasing force to actuate the switchmechanisms. Any suitable type of switch such as a snap action switch maybe used and they may be connected into electric circuits to effect, inthe case of a washing machine control, the several desired washingmachine operations. The switches are operated by a cam structurecomprising two cam disks I5 and. I6 shown in perspective in Fig. 10. Camdisk I5 is provided with a series ofrings of concentric arcuate slots ordepressions ll between which are lands l8, there being one ring for eachswitch l3. The

switch buttons l4 stand in line with such rings of slots and lands. Whena button is in a slot, it wil be in its out position. When engaged by aland between two slots, it will be actuated to its "in position. Thuseach ring of lands and slots forms in substance an annular cam foractuating a switch. The slots and lands for the several rings are ofdifferent numbers and arrangements to give desired switch actuations asmore fully explained hereinafter. Cam disk I6 is provided on its facewith arcuate ribs l9 (Fig. 2) which are positioned in slots I! of diskl5. Ribs H! are of less circumferential extent than the slots I! inwhich they are positioned so that disk I 6 may be turned to a limitedextent relatively to disk l5. In ribs iii are depressions or recesses 20(Fig. 10). Thus it will be seen that ribs l9 comprise depressions 20 andlands 2'! which also form cams for actuatingthe several switches I3, theswitch but-, tons l4 being out when in line with a depression 20 andbeing pushed in when in line with a land 2!. There are thus provided insubstance seven annular cams, one for each switch, each comprising landsand depressions on disks I 5 and H5. The slots or depressions .l'! inwhich projections l9 are located extend entirely through disk IS; theothers need be deep enough only to receive the switch buttons I4 exte dn l t roug theisk and are shown as not i Disk l5 has its hub 22 fixed tosleeve 6 by a key 23 so it turns with the sleeve. Disk 16 has its hub 24journaled on hub 22. The two disks are held frictionally in engagementwith each other with ribs l9 in slots IT by a spring 25 positionedbetween the end of hub 24 and the adjacent wall of a cup-shaped dial 26having a hub 21 fixed to sleeve 6 by key 23 and held against axialmovement by a suitable washer 28 fixed in an annular groove at the endof sleeve 6. The cup-shaped dial 2B is keyed to the periphery of disk l5as is indicated at 29 in Fig. 2. Attached to disk l6 by a plurality ofradially extending ribs 30 is a sector 3| carrying legends visiblethrough an arcuate window 32. Fixed to disk l6 by screws 33 which screwinto ribs 30 is a knob 34 for turning disk l6 relatively to disk l5.Knob 34 has feet 35 through which screws 33 pass. Feet 35 extend througharcuate slots 36 in dial 26, the slots being of a length to permit ofthe desired turning of disk Hi with respect to disk l5. In thisconnection it is to be understood that the friction between frictionring'9 and gear 4 is greater than that between disks l5 and I3 'so thatwhenever knob 34 is turned within the limits of slots 36, disk l5 willbe turned relatively to disk l5. The two disks will be turned togetherby turning dial 28, slipping the clutch ring 9 on gear wheel 4.

Referring now to Figs. 5 and 6, there is shown 'a single cam ring on anenlarged scale for the purpose of illustrating the adjustment of thedisks [5 and lb. The innermost cam ring is shown, the remaining camrings being broken away. Disk I5 has the slots ll between which are thelands 18. One slot ll extends throughout the major portion of thecircumference'of the disk as indicated by line A. Beneath disk I5 is thedisk l6 (shown shaded) having the lands 2i which project into such oneslot I! and between which are the depressions 28. In Fig. 5 disk I6 isshown as having been adjusted in a clockwise'direction to its extremeposition in this direction with respect to disk I5. Assume that thepoint a is the beginning of a cycle and that a. switch is positionedwith its actuating'button at this point. Assume also that the disks arebeing rotated together in a clockwise direction by the timing motor.From point a to point I) the switch button will be over a depression sothat it will be in its out position; from point D to point b, it will beover a land so it will be in its in position; from point I) to point'b",it will again be over a depression, and from point I) to point c, itwill again be over a land. Up to this'point, there have been fouractuations of the switch and it will be noted-that all these actuationshave been effected by cam means-on disk l5 alone. From point to point dis a depression, this being the length of slot l1 between the trailingend of the land on disk l and the leading end of the land on disk It.From point d to point e is a land on disk is and from point e to point1' is a depression on disk l6. Beginning atpoint f is a land whichcontinues until the cycle ends at point '9 I due to the operation ofother of the switches. It is to be noted particularly that the oneactuation from point 0 to point d is from a point on disk IE to a pointon disk l6 and that the remaining actuations are between points on'disk16.

Referring now to Fig. 6, disk 16 is shown as having been rotated in acounterclockwise direction with respect to disk 15 which has resulted inincreasing the length of the depression between 0 and d. The lengthofthe other depressions and lands have remained'the-same, Thus the lengthof time of the intermediate operation occurring between points 0 anddhas been increased. In the case of an automatic washing machine, thiswould be the washing period. The period of time between points 0 and din Fig. 5 would be the minimum washing time. The period of time betweenpoints 0 and d in Fig. 6 would be the maximum washing time. Byintermediate adjustments of the distance between points 0 and dintermediate lengths of washing times may be obtained. The cycle may berepeated by turning the two dials l5 and I6 as a unit to again bringpoint a on disk I5 into line with the switch buttons.

In the present instance, seven switches [3 are shown, this being thenumber required to carry out the successive operations required for onedesired cycle of operations. In the case of each switch, the positioningof it for the initial fixed length operation is eiiected by lands anddepressions on disk l5; the positioning of it for the final fixed lengthoperations is effected by lands and I depressions on disk l6; and thepositionin of it for the variable length intermediate operation iseffected by depressions between lands, one of which is on disk l5 andthe other on disk I6, In carrying out a cycle of operations an outposition of a switch 13 may be either an open position or a closedposition and likewise for an in position, Or a switch may close contactsin both its out and in positions. However, the arrangement of theswitches must be such that the intermediate variable length operation iscarried out when all switches are in their out positions.

Fig. '7 is a developed view of the cam surfaces. In Fig, 1, four of theswitches 13 are shown as being 011 one side of the shaft axis and threeas being on the other side which means that their initial or startingpoints for a cycle are displaced For purposes of illustration in Fig.'7, it has been assumed that all the switches are on the same side ofthe shaft axis, so their starting points are all together. The controlmechanism is laid out for a washing machine wherein washing is performedin a basket by an agitator after which the basket is rotated at highspeed for extracting water from the clothes. It may be a machine such asthat shown in my application Serial No. 551,096, filed August 25, 1944,and the controller may carry out the operations shown in suchapplication. There may be a soak period during which the clothes arefirst agitated in clean water and then spun to extract the Water fromthe clothes; next a wash period during which the clothes are firstagitated in soapy water and then spun to extract the soapy water fromthe clothes; and finally a rinse period during which the clothes areagain agitated in clean water and then spun to extract the water. It isthe wash agitate period which is adjustable as to length. The lands anddepressions for the "soak agitate and 'soak spin periods from a to carea part of disk H5. The lands and de-. pressions for the wash spinperiod, the rinse agitate period, and the rinse spin period from d to gare a part of disk Hi. The depressions for the adjustable wash agitateperiod from c to dare those between the trailin ends of the final landsof disk l5 and the leading ends of the initial lands on disk I5.

Figs; 8 and 9 representsections taken on line 8-8, Fig.7, showing thetwo disks l5 and IS in the two extreme adjusted positions-correspondingtoFigs5 and 6 respectively.

As is clear from Fig.7, all the switches are not actuated simultaneouslyat the beginning of an operation, some being actuated slightly ahead ofothers. This enables a desired change sequence in the circuitconnections for initiating a new operation of the machine. However, fromFig. 7 it will be seen that in the case of each cam ring, the washagitate" cycle begins at c at a depression and ends at the beginning ofa land at d.

Referring to Figs. 3 and 4, the dial 26 carries legends between points1.: and w for the initial operations by disk I5. This are corresponds inextent to the depressions and lands on diskv l5 for the initialoperation. The sector 31 carries legends for the intermediate adjustableoperation and the final operations of disk I5. Fig. 3 shows the dialadjusted for the minimum wash agitate period and Fig. 4 for the maximumwash agitate period.

Referring again to Fig. 7, after the machine stops at point g, the dialsmay be turned as a unit to a point h for a period which extends frompoint h to point z. This may be a period, in the case of a washingmachine, during which water in the machine is pumped to a drain.

In the particular case for which the present control mechanism was laidout, it was desired that beyond point 1 (Figs. 5, 6, and 7), theparticular switch actuated by the innermost cam ring be always in inposition. To this end, disk I5 is provided with a land beginning atpoint k which also operates such switch and with which the adjacent landon disk l6 may overlap. Such an arrangement may be provided inconnection with other of the cam rings if found desirable,

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof,but I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In an automatic control mechanism, a cam structure comprising a firstflat disk having therein on a plurality of concentric circles apinrality of concentric slots of lengths less than the circle on whichthey are located to provide a plurality of concentric lands anddepressions, a second flat disk adjacent to a surface of the first flatdisk having concentric projections positioned in said concentric slotsof lengths less than those of the slots in which they are located, saidprojections forming a plurality of lands, and means for turning thedisks relatively to each other to vary the positions of the lands of thetwo disks with respect to each other and to vary the lengths of thespaces between the lands of the first disk and the lands of the seconddisk.

2. In an automatic control for a cycle of operations, a cam structurecomprising a first fiat member having a plurality of rows of slotstherein which define cam depressions, surfaces of the member betweensaid slots defining cam lands, a second fiat member adjacent to asurface of the first fiat member having projections thereon positionedin said slots to form cam lands said projections being of lengths lessthan the slots, and means for moving said members relatively to eachother to vary the distances between the lands of the first fiat memberand the projections of the second fiat member whereby the extent of thecam depressions between such lands and projections are adjusted.

3. In an automatic control mechanism, a cam structure comprising a firstdisk having over an arc thereof spaced slots which define lands anddepressions for initial operations and a continuous slot on the circleof such are, a second disk having over an are spaced projections whichare positioned in said continuous slot and form lands and depressionsfor subsequent operations, the arc of said projections being of lesslength than the slot in which they are located, and means for turningsaid disks relatively to each other to provide a depression ofadjustable length between the lands of'the respective disks for anintermediate operation.

THOMAS T. WOODSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

